1. Technical Field
This disclosure relates to power-line modem networks, and more particularly, to an apparatus which permits a user to create a secure network over a powerline when employing powerline modems.
2. Description of the Related Art
Powerline modems communicate by employing a power network as a transmission medium. Since modems in a plurality of locations share the power network, the shared powerline is a medium that permits a powerline modem in one house to xe2x80x9cseexe2x80x9d the powerline modems (and their data) at other locations, for example, other homes. Since the powerline is shared and is common to all homes data can be accessed freely over the powerline.
Therefore, a need exists for an apparatus and method where a user programs the same private key into all powerline modems that need to be secured. A further need exists for an apparatus and method which permits the user to program the private key into the modems without using the powerline network. This method would prevent other modems on the network from maliciously gaining access to the private key.
The present invention creates a secure powerline modem network by using a portable security device which includes a powerline modem. The security device is capable of randomly generating a number and may have the ability to let the user enter a number. This number is preferably stored in the portable security device, and the number will be a private key (y) for all of the modems on a given secured network. Each modem that needs to be secured is disconnected from the powerline modem network and then connected to the portable security device. The portable security device will provide power to the powerline modem of the device to be secured on the network, while simultaneously isolating the device""s modem from the rest of the powerline modem network.
The portable security device then transmits the value of the private key to the other powerline modem device over their direct connection. Following this programming step, the powerline modem device is reconnected to the powerline network. Once all devices to be secured have been programmed in this manner, the master device on the network will transmit its public key (X). All powerline modems, both secured and unsecured, can hear this public key. Since all powerline modems that were programmed by the user""s portable security device have the same private key, they are all able to compute a same shared key (Y) by mathematically combining the master""s public key and their programmed private key (e.g., Y=(X)y). All communication on the secured network is then encrypted using this same shared key.
A portable security device for setting up secure powerline modem networks is disclosed. The portable security device includes a memory which stores a protocol for communicating with powerline modem devices, and a socket configured to receive a power cord from a powerline modem device. A number assigning device transmits a private key to powerline modem devices such that the private key is stored in the powerline modem devices and is used to associate a plurality of powerline modem devices and exclude unauthorized powerline modem devices.
Another portable device for communicating with powerline modems includes a memory which stores a protocol for communicating with powerline modem devices. A communication link is configured to communicate with a powerline modem device such that when a communication connection is made with the powerline modem device an entire available bandwidth of the powerline modem device is available for communication.
A relay may be connected between the power line and the socket, which switches off power to the powerline modem device to prove that the portable device is actually connected to the powerline modem device. A filter is preferably coupled to the power line, which permits power to pass therethrough but filters out other frequencies.
These and other objects, features and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.